Incidental 16 is a fish who makes cameo appearances throughout the series, starting in the episode "Ripped Pants."
He is a dark bluish-gray fish. He has lavender colored lips, several dark purple spots on his body, and big white eyes with black pupils. He wears lime green shorts.
He is first seen in the episode "Ripped Pants" where he watches a weight lifting and is part of the audience when SpongeBob sings a song about ripping his pants. He also makes appearances in other episodes, usually in crowds along with other Bikini Bottomites.